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Common causes of camshaft timing belt failure on the above vehicles are due to incorrect operating tension, or ingress of dirt, water, or debris entering the timing belt cover. Predominantly on Fiesta models a high percentage of camshaft timing belt failures occur after the ancillary poly ‘V’ drive belt has failed, where strands of material off the broken belt have entered the timing belt cover. This is especially so where an ancillary belt has been fitted that does not contain “Kevlar” based materials. It is therefore important to always remove the timing belt cover to check for belt debris if the ancillary belt has failed. Any contamination that enters the timing belt cover can become compressed between the surfaces of the camshaft timing belt and drive pulleys. This causes wear to both the belt teeth, backing surface, and damage to the drive pulleys, resulting in premature failure of the camshaft timing belt. Later engines have modifications to improve the sealing of the belt cover around the crankshaft pulley, to reduce the level of outside contamination. Incorrect tensioning of the belt during installation will adversely affect the life of the belt. Before fitting a new belt it is important to check and observe the following points :- 1) Right Hand Inner Wing Splash Shield (Fiesta, Escort, Mondeo) This must be fitted and undamaged. 2) Timing Belt Cover Check that all components of the cover are fitted and undamaged. Ensure the latest type of modified cover is fitted. 3) a) Toothed Drive Pulleys Check that the tooth profiles are not worn or damaged. On vehicles built before January 1994 special attention should be given to the nylon toothed pulley situated below the camshaft pulley in a clockwise position on the belt drive (see diag item 4). This should be changed to a modified steel pulley (Ford No. 7053802) plus bolt (6701537). Ensure that the Camshaft and Injection Pump sprockets are free to rotate on the drive locations when the retaining bolts are slackened off. b) 4) a) b) c) Water Pump, Idler and Tensioner Pulleys Check that the belt running surfaces are not worn or damaged. Check that the flanges are running true and not damaged. Check that the water pump, and pulley bearings are in good condition, to ensure correct belt alignment. 5) Crankshaft Pulley The toothed pulley is in two parts. The rear section (Injection Pump Drive) is located onto the crankshaft by a small drive pin. The front section (Camshaft and “Poly V” belt drive) engages onto the rear pulley via a small vee protrusion on the rear face. Should the central fixing bolt for the crankshaft pulley come loose, or an old bolt re-used (Stretch bolt design), it is possible for fretting to take place damaging the locations. The crankshaft and camshaft pulleys can then move out of timing alignment, resulting in valve and piston contact damage. Replacement Procedure As the vehicle is fitted with two timing belts, one to drive the Camshaft, and one to drive the Injection Pump drives, which are driven off the crankshaft pulley, it is strongly recommended that both belts are replaced at the same time. NOTE: Special tools are required to lock the crankshaft, camshaft, and injection pump in the correct angular location when changing the belts, to ensure correct timing position. IMPORTANT: Ensure the engine is cold (not run for 4 hours) before commencing working as this will affect the setting of the timing belt tension and could lead to premature failure. Continued . . . .

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Checking Timing An access plug is provided in the cam drive belt cover so that camshaft timing can be checked without removal of the cover or any other parts. 1. Remove the access plug from the cam drive belt cover. 2. Rotate the crankshaft so that the No. 1 piston is rising on compression stroke. 3. Set the crankshaft to TDC by aligning the timing mark on the crank pulley with the TC mark on the belt cover. Always turn the engine in the direction of normal rotation (clockwise, as viewed from the front). Backward rotation may cause the timing belt to jump time, due to the arrangement of the belt tensioner. 4. Look through the access hole in the belt cover to make sure that the timing mark on the cam drive sprocket is lined up with the pointer on the inner belt cover. 5. Install the belt cover access plug. Adjusting Timing Belt SPECIAL SERVICE TOOL(S) REQUIRED Description Crankshaft Belt Tension Adjusting Tool T74P-6254-A 1. Remove the outer timing belt cover as outlined in this section. CAUTION: Attempting to adjust timing belt tension without loosening spring pivot bolt will break Crankshaft Belt Tension Adjusting Tool T74P-6254-A when relieving tension on the belt. 2. If belt timing or tension is incorrect, loosen timing belt spring pivot bolt. 3. Hold tensioner with Camshaft Belt Tension Adjusting Tool T74P-6254-A. 4. While holding tensioner, loosen adjusting bolt and gradually release spring tension. Loosening Timing Belt Tensioner, 2.3L Tool Number 8 — 5. Using adjusting tool, pry tensioner away from belt. While holding, tighten adjusting bolt. There should be no tension on belt. Camshaft Timing Belt, 2.3L I-4 Timing Mark on Camshaft Sprocket Remove the bolts holding the crankshaft position sensor in place and pull the sensor assembly free of the dowel pin. 7. Remove the crankshaft pulley , crankshaft pulley hub and timing belt guide. 8. Remove the drive belt and inspect it for wear or damage. If the belt is damaged, replace it. 9. Remove one spark plug from each cylinder. 10. If not done: a. Loosen tensioner adjusting bolt. b. Using Camshaft Belt Tension Adjusting Tool T74P-6254-A, pry tensioner clockwise against spring tension as far as possible. c. Tighten adjusting bolt to hold tensioner in released position. 11. Align crankshaft so number one piston is at TDC (top dead center) as indicated by timing mark. 12. Line up camshaft sprocket timing mark with inner timing belt cover timing mark and key is pointing down.

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The above application is prone to the timing belt teeth lifting off the belt in service due to operating the belt with insufficient tension. The following instructions have been produced to assist in the fitting of your new timing belt, giving simple hints and tips, which should help avoid problems caused by adopting an incorrect fitting / adjustment procedure. For instructions for the removal of the engine components required to gain access to the timing belt, please refer to the vehicle workshop manual. Note:- Incorrect tension of the timing belt, can lead to the teeth lifting from the belt, resulting in belt failure, and subsequent major engine damage. Special Tools Required: 1) Timing belt tension gauge, (accurately calibrated), Part No’s: either Rover KM4088 or Borroughs BT33-86F 2) Two 8mm Allen keys (for tensioner adjustment) 3) Short length of round steel bar (for flywheel timing location) Fitting Procedure: 1) Before the old timing belt is removed, the crankshaft should be rotated clockwise to align the timing mark on the crankshaft pulley with the edge of the metal bracket, which forms part of the lower timing belt cover (See I). To lock the crankshaft in this position, which is 90 degrees before top dead centre, insert a steel rod of the correct diameter into the hole on the gearbox / engine adaptor plate, positioned on the front facing lower edge of the cylinder block (See diagram B), and locate with the corresponding hole in the flywheel. The timing marks on the camshaft gears should now be aligned at the 3 o’clock position for the left hand gear, and the 9 o’clock position for the right hand gear (See II). Undo the timing belt tensioner Allen bolt and remove tensioner. The old timing belt can now be removed (See III). Check the condition of the geared teeth on the camshaft, crankshaft, and water pump drives. Check the tensioner, water pump, and idler bearings. Fit the new timing belt over the drive gears, ensuring the timing marks set at ‘I’and‘II’ have not moved. Refit the tensioner using the anti-slip washer ‘IV’ supplied with the new timing belt. The anti-slip washer should be fitted between the tensioner and the backplate, with the abrasive side facing towards the tensioner. Note: A new anti-slip washer must always be fitted. Non modified vehicles will not have the anti-slip washer fitted. Rotate the tensioner, using the Allen key drive to set the initial pre-load tension, sufficient to prevent the timing belt from slipping over the toothed drives, then tighten the Allen bolt to 45Nm.